The invention relates to a gas generator of sheet-metal constructional type for a motor vehicle passenger protection device.
Such a gas generator of the type described is known from DE-A1-41 21 039. Said gas generator is constructed concentrically, a combustion chamber with a gas-generating charge being disposed around an ignition chamber with an igniter and an ignition charge and the combustion chamber being surrounded by an expansion chamber. The expansion chamber contains a dust-collecting space and a cooling/expansion space. The gas escaping through discharge apertures from the combustion chamber is divided into a primary flow and a secondary flow. The primary flow is forced into the dust-collecting space, while the purified gas is conveyed through the cooling/filter space into the gas pocket of the air bag. By increasing the velocity of the escaping gas, a high separation efficiency is attainable. This is achieved by the intrinsic discharge energy of the gas.